Abstract Despite improvements in treatment regimens and technology, less than 20% of adults with type 1 diabetes (T1D) achieve glycemic targets. Sleep is increasingly recognized as a potentially modifiable target for improving glycemic control. Diabetes distress, poor self-management behaviors, and reduced quality of life (QoL) have also been linked to sleep variability and insufficient sleep duration. The American Diabetes Association Standards of Medical Care in Diabetes incorporated sleep as an important component of the medical evaluation in persons with diabetes. However, no specific recommendation was given as to how to improve sleep. A significant gap of knowledge exists regarding the effects of sleep optimization on glycemic control in T1D. The purpose of this study is to determine the efficacy of a T1D-specific sleep optimization intervention (Sleep-Opt) on the primary outcomes of sleep variability, sleep duration and glycemic control (A1C); other glycemic parameters (glycemic variability, time in range), diabetes distress, self-management behavior, QoL, and other patient reported outcomes in working-age adults with T1D and habitual increased sleep variability or short sleep duration. To achieve these aims, we propose a randomized controlled trial in 120 working age adults (18 to 65 years) with T1D. Participants will be screened for habitual sleep variability (> 1 hour/week) or insufficient sleep duration (< 6.5 hours per night). Eligible subjects will be randomized to the Sleep-Opt group or healthy living attention control group for twelve weeks. A one-week run-in period is planned, with baseline measures of sleep by actigraphy (sleep variability and duration), glycemia (A1C and related glycemic measures: glycemic variability and time in range using continuous glucose monitoring), and other secondary outcomes: diabetes distress, self-management behaviors, quality of life and additional patient- reported outcomes. Sleep-Opt is a technology-assisted behavioral sleep intervention that we recently developed that leverages the rapidly increasing public interest in sleep tracking by consumers (+500% in 3 years). Our behavioral intervention employs four elements: a wearable sleep tracker, didactic content, an interactive smartphone application, and brief telephone counseling. The attention control group will participate in a healthy living information program. At midpoint (Week 6) completion (Week 12) and post-program (Week 24), baseline measures will be repeated to determine differences between the two groups and sustainability of the intervention.